Number Keys not Changing View
You have to use the numpad keys, not the number keys. However, if you are on a laptop or similar device that does not have a numpad, you can do the following.

Go to File > User Preferences > Input tab and check Emulate Numpad. This will allow the number keys at the top of your keyboard to function as numpad keys. You will, however, lose the functionality to switch layers, the shortcut to add a Subdivision surface object modifier, and whatever else they are good for. Make sure to click Save User Settings at the bottom of the User Preferences panel. This will make it so that you can use these keys every time you open Blender, rather than having to change the user preferences every time.

The File menu:



The User Preferences window: